Tuesday, September 18, 2012

Asian frogs becoming extinct before they can be identified, biologists warn

Scientists fear
amphibian destruction will be disastrous, with many species disappearing
uncatalogued.

Frogs and other amphibians are being wiped out at such a
rapid rate across Asia that many are going extinct before scientists even have
a chance to identify them as new species, biologists warned at an international
conservation meeting in South Korea this week.

The scale of the destruction – caused by habitat loss,
disease, pollution and other factors – is hard to quantify, but scientists fear
the result will be disastrous. Amphibians have been suffering a wave of
devastation all around the world, in part because of the spread of the fungal
disease Batrachochytrium dendrobatidis, known as BD or chytrid fungus, which
has wiped out whole populations within the space of a few years.

But while conservation and monitoring efforts have so far
focused on the Americas and Europe, little work has yet been done in the
world's most populous continent, with the result that many amphibian species
there are as yet uncatalogued and unstudied. For instance, according to one
researcher, there are probably at least three to four times as many amphibian
species in India alone as are currently catalogued.

Frogs and other amphibians are among the most threatened
creatures in the world today – globally, at least a third, probably 40%, of
amphibian species are in urgent danger of extinction, making a total of more
than 2,000 species of amphibian so far documented to be officially
"threatened", "endangered" or "vulnerable",
classifications used by scientists to describe the level of threat. "This
is higher than any other terrestrial animal," said Jaime García-Moreno,
executive director of the Amphibian Survival Alliance.

The plight of frogs and other amphibians is of particular
concern to scientists because many think the devastation afflicting them could
be a foretaste of that in waiting for other creatures. Their physiognomy makes
amphibians particularly sensitive to small changes in their environment,
including temperature changes such as global warming, and to water and air
pollution.

This sensitivity, some scientists believe, could be behind
the sudden and unexpected extinction of certain species even from
well-protected areas. Waldman pointed to the golden toad of Costa Rica which
"disappeared from a pristine habitat".

Scientists could also learn more about the deadly chytrid
disease from studying Asia, noted Mi-Sook Min, research professor at Seoul
National University. Some indicators suggest the disease could even have come
from the continent, as most cases to date have been found in other continents
which may indicate a long history in Asia whereby amphibians have evolved to
live with the disease. However, there are also indications in other research
that the disease could have been existing in Latin America since the 1880s.

The scientists, presenting their work at the World
Conservation Congress, the quadrennial meeting of the International Union for
Conservation of Nature, in Jeju this week, called for more research into
amphibians in Asia as a matter of urgency.